Asteroid Juno

Juno

Juno (3) is the third asteroid discovered in the solar system, named after Juno, the wife of Jupiter. This is one of the main asteroid main belt. Juno was discovered by Carl Ludwig Harding Observatory Lilienthal, near Bremen, September 1, 1804 using a simple 5-cm telescope aperture. Juno revolves around the Sun in 4.36 years with a semi-major axis of about 400 million km and an eccentricity of 0.26. Juno's orbit changed in 1839, perhaps due to an impact. Images taken in adaptive optics to Mount Wilson Observatory (USA) show that the small planet about 230 km average diameter was completely disfigured by a collision that created a huge crater size 100 km like a bite. This adaptive optics system has resulted in a remarkably clear view of Juno, reducing interference with the Earth's atmosphere.

Image: The artist representation on the image to the right shows the front, a huge impact crater.(David A. Aguilar, Harvard-Smithsonian Center for Astrophysics).

nota: The interplanetary space is far from empty, it is littered with dust and matter dating from the creation of the solar system. Asteroids are mainly located in the main belt between the orbits of Mars and Jupiter (between 300 and 600 million km from the Sun). There are hundreds of thousands of objects listed. All objects could have formed a planet in the area but the gravitational perturbations of Jupiter did not permit.

Juno

Characteristics

Dimensions

320x267x200 km

Mean radius

≈233 km

Mass

2.82±0,12×1019 kg

Rotation period

7.21 hr

Temperature

≈163 K

Aphelion

502.08×106 km

Perihelion

328.87×106 km

Semi-major axis

399.48×106 km

Axial tilt

51°

Orbital period

4.37 a or 1595.4 d

Average orbital speed

17.93 km/s

Eccentricity

0.2568

Inclination to Ecliptic

12.968°

Longitude of ascending node

169.96°

Argument of perihelion

247.93°

Asteroids

Approximatedimensions

Discovery date

Ceres 1

974.6 km

1801

Pallas 2

582×556×500 km

1802

Vesta 4

572.6x557.2x446 km

1807

Hygiea 10

530x407x370 km

1849

Sylvia 87

384x262x232 km

1866

Hektor 624

370x195x195 km

1907

Europa 52

360x315x240 km

1858

Eunomia 15

357x355x212 km

1851

Davida 511

357x294x231 km

1903

Interamnia 704

350.3x303.6 km

1910

Camilla 107

344x246x205 km

1868

Juno 3

320x267x200 km

1804

Cybele 65

302x290x232 km

1861

Hermione 121

268x186x183 km

1872

Euphrosyne 31

255.9 km

1854

Chariklo 10199

248x258 km

1997

Iris 7

240x200x200 km

1847

Psyche 16

240x185x145 km

1852

Daphne 41

239x183x153 km

1856

Kalliope 22

235x144x124 km

1852

Amphitrite 29

233x212x193 km

1854

List of the largest asteroids.

nota: The eccentricity defines the shape of an elliptical orbit, it varies between 0 and 1. 0 for circular orbits. A high eccentricity decreases the minor axis (perihelion) and increases the larger axis (aphelion), but does not change the major axis.